This application claims priority of Taiwan patent Application No. 90224279, filed on Dec. 31, 2001.
1. Field of the Invention
This invention relates to a wood planing machine, more particularly to a wood planing machine with a height adjusting unit for adjusting the height of a work table of the wood planing machine.
2. Description of the Related Art
FIGS. 1 and 2 illustrate a conventional wood planing machine for planing a wooden work-piece (not shown). The planing machine includes a main support 11 defining a mounting wall 123 that faces upwardly and inclinedly relative to a horizontal plane, and a work table 10 having a horizontal plate 12 that defines the horizontal plane, and front and rear side plates 122 that project downwardly from the horizontal plate 12 and that are mounted slidably on the mounting wall 123 so as to permit the work table 10 to be movable in a longitudinal direction, which, in turn, permits adjustment of the thickness of the wooden work-piece to be planed. A height adjustment unit is mounted on the main support 11, and includes a threaded part 131 that is secured to a bottom of the horizontal plate 12, and a handle wheel 134 with a screw rod 133 that is secured to the main support 11 and that threadedly engages the threaded part 131 so as to permit sliding movement of the work table 10 together with the threaded part 131 in the longitudinal direction. The conventional planing machine is disadvantageous in that the thread formed in the threaded part 131 tends to be worn or damaged by the screw rod 133 due to vibration of the planing machine during that planing operation. Moreover, the side plates 122 of the work table 10 are mounted on the mounting wall 123 via a wedging mechanism which is difficult to be formed on the side plates 122 and the mounting wall 123.
Therefore, it is an object of the present invention to provide a wood planing machine that is capable of overcoming the aforesaid drawbacks associated with the prior art.
Accordingly, a wood planing machine of this invention comprises: a main support including a base that has opposite front and rear ends and opposite left and right ends, and front and rear side walls that respectively and uprightly project from the front and rear ends of the base, that cooperately confine a mounting space therebetween, and that define a top open end of the main support opposite to the base; a mounting seat disposed in the mounting space and extending between and secured to the front and rear side walls, the mounting seat having an inclined mounting wall that extends inclinedly relative to a horizontal plane in a longitudinal direction from the right end of the base toward the left end of the base and that is formed with an elongated slot which extends in the longitudinal direction; a sliding member that is slidably mounted on the inclined mounting wall within the mounting space, and that has a top wall extending in a horizontal direction parallel to the horizontal plane, the sliding member being slidable on the inclined mounting wall in the longitudinal direction; a work table defining the horizontal plane, covering the top open end of the main support, and secured to the top wall of the sliding member so as to be co-slidable with the sliding member in the longitudinal direction; and a height adjusting unit including a screw unit, and a threaded part mounted securely on the sliding member via the screw unit which extends through the elongated slot, the sliding member and the threaded part so as to permit concurrent sliding movement of the sliding member and the threaded part on the inclined mounting wall in the longitudinal direction. The height adjusting unit further includes a screw rod that is rotatably mounted on the mounting seat, that extends in the longitudinal direction, and that threadedly engages the threaded part so as to move the work table together with the sliding member and the threaded part in the longitudinal direction upon rotation.